In addition to polyvinyl chloride, PVC pastes contain plasticizers, filler, pigments, stabilizers and fire retardants. The pastes are delivered to the processing station by pumps and pipelines. In the event of a production changeover, these pumps and pipelines can be cleared of PVC-containing residues having a lacquer-like to pasty consistency only by means of a solvent, preferably an aromatic gasoline. The solvent-containing waste pastes thus obtained usually have a solids content of about 60% by weight and must be processed under sub-contract in special plants by distilling out the solvent, whereby, depending upon the residual solvent content, a highly viscous or crusty, bubble-filled residue is obtained which has to be disposed of as special waste material. There is no known way of modifying the recovery process so that the residues can be used over again.